Methicillin-resistant Staphylococcus aureus isolated from an intensive care unit in Minas Gerais, Brazil, over a six-year period

ABSTRACT To characterize methicillin-resistant Staphylococcus aureus isolates from an intensive care unit of a tertiary-care teaching hospital, between 2005 and 2010. A total of 45 isolates were recovered from patients admitted to the intensive care unit in the study period. Resistance rates higher than 80% were found for clindamycin (100%), erythromycin (100%), levofloxacin (100%), azithromycin (97.7%), rifampin (88.8%), and gentamycin (86.6%). The SCCmec typing revealed that the isolates harbored the types III (66.7%), II (17.8%), IV (4.4%), and I (2.2%). Four (8.9%) isolates carried non-typeable cassettes. Most (66.7%) of the isolates were related to the Brazilian endemic clone from CC8/SCCmec III, which was prevalent (89.3%) between 2005 and 2007, while the USA100/CC5/SCCmec II lineage emerged in 2007 and was more frequent in the last few years. The study showed high rates of antimicrobial resistance among methicillin-resistant S. aureus isolates and the replacement of Brazilian clone, a well-established hospital lineage, by the USA100 in the late 2000s, at the intensive care unit under study.

Mielopatia sinalizando o diagnóstico tardio da infecçãopor HtlV: um relato de caso / Myelopathy signaling the late diagnosis of HIV infection: a case report

A infecção pelo vírus T-linfotrópico humano (HTLV) caracteriza-se como uma doença sexualmente transmissível (DST), que pode também ser adquirida pelas vias parenteral e vertical. Subdivide-se em dois tipos: o HTLV-I, relacionado com doenças como mielopatia associada a HTLV/paraparesia espástica tropical (HAM/TSP) e a leucemia/linfoma de células T do adulto (ATL). Já o HTLV-II ainda não foi correlacionado cientificamente com nenhuma patologia na atualidade. Seu diagnóstico é realizado pela triagem sorológica para a detecção de anticorpo anti-HTLV-I/II, sendo o exame confirmatório o western blot. Neste contexto, o objetivo do presente estudo foi descrever um relato de caso em que a mielopatia foi a manifestação clínica sinalizadora da infecção pelo HTLV, em consequência do diagnóstico tardio da infecção por este patógeno, na qual a paciente apresentou os sintomas, progrediu lentamente e recebeu o diagnóstico apenas no último estágio da patologia (HAM/TSP), quando se tornou cadeirante. Embora a paciente realize na atualidade a terapêutica proposta e o acompanhamento ambulatorial segundo o protocolo estabelecido para o manejo desta infecção viral, membros de sua família também foram avaliados e diagnosticados e apenas um se apresentou positivo para a infecção. Este estudo visa demonstrar a importância do rastreio laboratorial para a infecção pelo HTLV, na mesma dimensão do diagnóstico da sífilis e do HIV, de modo que o mesmo não ocorra de forma tardia, quando associado a suas manifestações clínicas nos pacientes ou a infecções oportunistas relacionadas.

The human T-lymphotropic virus (HTLV) is characterized as a sexually transmitted disease (STD), it can also be transmitted by parenteral and vertical routes. It is subdivided into two types: the HTLV-I related diseases such as myelopathy/tropical spastic paraparesis (HAM/TSP) and adult T-cell leukemia/lymphoma (ATL). HTLV-II has not been scientifically correlated with pathology yet. This diagnosis is made by serological screening for detection of HTLV antibody, and the western blot confirmatory test. In this context, the objective of this study was to describe a case in which myelopathy was signaling to the clinical manifestation of HTLV, as a result of delayed diagnosis of infection by this pathogen in which the patient had symptoms progressed slowly and received diagnosis only in the last stage of pathology (HAM/TSP), becoming a wheelchair user. Although nowadays the patient performs the therapeutic proposed and outpatient treatment according to the established protocol for the management of this viral infection, members of her family were also diagnosed and only one had a positive diagnosis of infection. This study aims to demonstrate the importance of laboratory screening for HTLV infection, in the same dimension of the diagnosis of syphilis and HIV, so that it does not occur so late, when it is associated to clinical manifestations in patients or related opportunistic infections

Accuracy of phenotypic methicillin susceptibility methods in the detection of Staphylococcus aureus isolates carrying different SCCmec types

A total of 138 isolates, 118 methicillin-resistant Staphylococcus aureus (MRSA) isolates (staphylococcal cassette chromosome type II, 20 isolates, type III, 39 isolates and type IV, 59 isolates) and 20 methicillin-sensitive S. aureus isolates were evaluated by phenotypic methods: cefoxitin and oxacillin disk diffusion (DD), agar dilution (AD), latex agglutination (LA), oxacillin agar screening (OAS) and chromogenic agar detection. All methods showed 100 percent specificity, but only the DD tests presented 100 percent sensitivity. The sensitivity of the other tests ranged from 82.2 percent (OAS)-98.3 percent (AD). The LA test showed the second lowest sensitivity (86.4 percent). The DD test showed high accuracy in the detection of MRSA isolates, but there was low precision in the detection of type IV isolates by the other tests, indicating that the genotypic characteristics of the isolates should be considered.